'America's Got Talent' aims to stir it up for Season 9

In the sunshine-yellow green room, Howie Mandel is trying to set up two single people.

"Think of me as Tinder-Man," he says

On cue, fellow returning "America's Got Talent" judges Howard Stern, Heidi Klum and Mel B wander in, after a taping for the NBC series at the Dolby Theatre, with acts, including an awkward comedian telling diaper jokes. He is among would-be contestants in auditions that begin tonight.

Klum hated that comedian. "I had no problem with his awkwardness. I just didn't like his jokes," she says. Stern and Mandel helped send the guy through.

Performance artist Kenichi Ebina took home the big prize last year, and although ratings were up 6 percent to 12 million viewers, producers are trying to shake up the show's formula for Season 9, which premieres tonight.

Enter the "Golden Buzzer," a last-minute rescue by a judge. And this year, talent can submit videos to the Today show. The top three entries will perform on Today, and fans can vote oneinto the live shows.

"Shows can get stale, let's face it," Stern says. "We take that into account."

Host Nick Cannon is back, too, but Las Vegas Week is moving to New York, to accommodate Stern, who joined "AGT" in 2012.

The weirdest acts they've seen this year? One "was setting a record for the most spiders put on his face," Mandel says. "They were poisonous tarantulas. Then Heidi put them on her."

Does that make Mel B the normal one? Hardly. During one taping, the judges repeatedly tried to ax an act, "and we're buzzing and buzzing," Klum says.

Under the desk, a member of the show's technical team finds a strange wire, says Mandel, "And where does the wire go to? To Mel. Mel is charging her phone. She pulled out a plug. And that's the one that just told you she's the normal one."